#include<stdio.h>
#include<math.h>
int main()
{
    double y;
    int x,m;
    for (y=10 ;y>=-10 ;y--)
    {
    m= 2.5*sqrt(100-y*y);
    for(x=1;x<30-m;x++)
    printf(" ");
    printf("*");
    for (;x<30+m;x++)printf(" ");

printf("*\n");
    }
}
/*吴石磊*/